Abstract
Ellipsometry, electron microscopy, and x-ray photoelectron spectroscopy data indicate that, during HfO 2 deposition onto silicon, the native oxide reacts with the HfO 2 deposit to form an amorphous intermediate layer which differs in refractive index (≃1.6) from both HfO 2 (1.9-2.0) and SiO 2 (1.46). Thermodynamic analysis of the Si-SiO 2-HfO 2-Hf system shows that Si is in equilibrium with Si/HfO 2 - y only at low oxygen pressures. Starting at a certain oxygen pressure (equivalent to the formation of a native oxide layer), the equilibrium phase assemblage is Si/HfSiO 4/HfO 2 - y.
Original language | English |
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Pages (from-to) | 965-970 |
Number of pages | 6 |
Journal | Inorganic Materials |
Volume | 44 |
Issue number | 9 |
DOIs | |
Publication status | Published - Sep 2008 |